1. Field of the Invention
The present invention relates to a gasket for a door mirror interposed between a mirror base of a door mirror and a car body.
2. Related Background Art
In general, a door mirror of a car is mounted so that a mirror base supporting a mirror body is fixed to a mounting seat set on a door or the like of the car body with such fastening devices as bolts and nuts and so that a gasket is normally interposed between the mirror base and the mounting seat of the car body. The door mirror gasket of this type is made of a flexible material, such as polyvinyl chloride or the like, but there is a small clearance made relative to the mounting seat of the car body. Therefore, water might enter the car interior through the clearance during rain or car wash. Air in the car could be forced out through the clearance during a run of the car to make sort of wind noise.
Thus the conventional door mirror gaskets of this type are provided with a seal structure for sealing the clearance relative to the mounting seat of the car body. FIG. 8 shows the seal structure of a door mirror gasket according to a conventional example, in which a rib R continuously extending along the circumference of the gasket G projects on an opposed surface of gasket G, which will face the mounting seat of the car body. Strip seal sponge S covering this rib R is affixed to the opposed surface of the gasket G.
In this conventional seal structure of the door mirror gasket, when the gasket G is interposed between the unrepresented mirror base and the mounting seat of the car body and is pressed against the mounting seat, the seal sponge S is compressed in the directions along its thickness to collapse and, particularly, thinly collapse at the rib R, thereby sealing the clearance between the mounting seat of the car body and the opposed surface of the gasket G.
Another conventionally known seal structure for door mirror is a structure of sealing the clearance with an annular packing, instead of the seal sponge (ex. JP08-188087A).